Matthew Sykes

Max Shtein

Associate Professor

mshtein@umich.edu

2014 HH Dow

T: (734) 764-4312

Bio

Publications

Group


mesykes@umich.edu
B.S. Materials Science and Engineering, University of Illinois

My research focuses on strongly bound electron-hole pairs (excitons) that are generated during the absorption/emission process in organic materials, and their coupling to optical modes inside ultrathin organic photovoltaics (OPVs) and organic light-emitting diodes (OLEDs). Through hybridization with surface plasmon polaritons in thin metal cavities or by tuning their interaction with neighboring media, it is possible to modify exciton formation, recombination, and diffusion dynamics. I employ both experiments and classical electromagnetic theory to study the effects such near-field interactions have on device performance. By controlling optical interactions, I seek to break some of the fundamental tradeoffs intrinsic to organic optoelectronic devices.


Publications:

 

  1. “Ultrafast charge-transfer dynamics at the boron subphthalocyanine chloride / C60 heterojunction: Comparison 
between experiment and theory,” D. E. Wilcox, M. H. Lee, M. E. Sykes, A. Niedringhaus, E. Geva, B. D. 
Dunietz, M. Shtein, and J. P. Ogilvie, J. Phys. Chem. Lett. (In Press). 

  2. “Effect of axial halogen substitution on the performance of subphthalocyanine based organic photovoltaic 
cells,” S. E. Morris, D. Bilby, M. E. Sykes, H. Hashemi, M. J. Waters, J. Kieffer, J. Kim, and M. Shtein, 
Organic Electronics, 2014, 15, 3660. 

  3. “Heterodyne-detected and ultrafast time-resolved second-harmonic generation for sensitive measurements of 
charge transfer,” D. E. Wilcox, M. E. Sykes, A. Niedringhaus, M. Shtein, J. P. Ogilvie, Opt. Lett. 2014, 39, 
4274. 

  4. “Universal design principles for small molecular cascade heterojunction solar cells with high fill factor and 
internal quantum efficiency approaching 100%,” A. Barito, M. E. Sykes, B. Huang, D. Bilby, B. Frieberg, J. 
Kim, P. F. Green, and M. Shtein, Adv. En. Mat. 2014, DOI: 10.1002/aenm.201400216 

  5. “Broadband plasmonic photocurrent enhancement in planar organic photovoltaics embedded in a metallic 
nanocavity,” M. E. Sykes, A. Barito, J. Amonoo, P. F. Green, and M. Shtein, Adv. En. Mat. 2014, 4, 1301937. 

  6. “Reduction of open circuit voltage loss in a polymer photovoltaic cell via interfacial molecular design: Insertion 
of a molecular spacer,” D. Bilby, J. Amonoo, M. E. Sykes, B. Frieberg, B. Huang, J. Hungerford, M. Shtein, P. 
F. Green, and J. Kim, Appl. Phys. Lett. 2013, 103, 203902. 

  7. “Recovering lost excitons in organic photovoltaics with a transparent dissociation layer,” A. Barito, M. E. 
Sykes, D. Bilby, J. Amonoo, Y. Jin, S. E. Morris, P. F. Green, J. Kim, and M. Shtein, J. Appl. Phys. 2013, 113, 
203110. 

  8. “Influence of exciton lifetime on charge carrier dynamics in an organic heterostructure,” K. Agrawal, M. E. 
Sykes, K. H. An, B. Freiberg, P. F. Green, and M. Shtein, Appl. Phys. Lett. 2013, 102, 113304. 


Selected Presentations:

  1. “Universal design principles for cascade heterojunction organic photovoltaics with broad spectral coverage and power conversion efficiency greater than 8%,” A. Barito, M. E. Sykes, D. Bilby, B. Huang, K. L. Agrawal, B. X. Dong, B. Frieberg, P. F. Green, J. Kim, and M. Shtein, MRS Fall Conference (Boston, December 2014) 

  2. “Effect of copolymer chain architecture on active layer morphology and device performance,” J. Amonoo, A. Li, M. Sykes, B. Huang, E. Palermo, A. McNeil, M. Shtein, P. F. Green, APS Meeting (Denver, March 2014). 

  3. “Exciton dissociation layers for maximizing current generation in organic photovoltaics,” A. Barito, M. E. Sykes, S. E. Morris, J. Amonoo, D. Bilby, J. Kim, P. F. Green, and M. Shtein, MRS Spring Conference (San Francisco, April 3, 2013)
  4. “Optically enhanced exciton diffusion in OPVs,” M. Sykes, A. Barito, D. Bilby, J. Kim, and M. Shtein, MRS Spring Conference (San Francisco, April 2, 2013)
  5. “Optical field modulation of current in organic light emitting diodes,” K. Agrawal, M. Sykes, K.H. An, and M. Shtein, MRS Spring Conference (San Francisco, April 12, 2012)
  6. “Tailoring plasmonic and dielectric nanostructures for angle-selective photon management in organic photovoltaics,” M. Sykes, B. Roberts, N. Dissanayake, K.H. An, M. Shtein and P.C. Ku, EFRC External Review (Baltimore, Jan. 11, 2012) 

  7. “Plasmon‐enhanced exciton generation in organic photovoltaics,“ M. Sykes, B. Roberts, K.H. An, P.C. Ku, M. Shtein, Science for our Nation’s Energy Future: EFRC Summit and Forum (Washington D.C., May 25, 2011) 

  8. “High-efficiency surface plasmon energy harvesting using optimized organic photovoltaics,” M. Sykes, B. Roberts, K.H. Ah, P.C. Ku, M. Shtein, MRS Spring Conference (San Francisco, April 24, 2011)